[R] Coloring counties on a full US map based on a certain criterion

[Sarah Goslee]

On Fri, Jan 13, 2012 at 1:41 PM, Dimitri Liakhovitski
<dimitri.liakhovitski at gmail.com> wrote:
> Thank you somuch, Sarah. I tried, and it's working just wonderfully
> (code below).
> One last question, if I may: is it possible to get rid of borders
> between counties (just leave the fill)? I did not find this argument
> in help...

But the help does say that additional arguments are passed to lines(),
so you can use lty=0.

That can leave white bits between counties if the areas don't line up
precisely, so I think it looks better with the lines in black.

Sarah

> Thank you!
> Dimitri
>
> ### My criterion for all counties.:
> allcounties<-data.frame(county=map('county', plot=FALSE)$names)
> allcounties$group<-c(rep(1:6,513),rep(1,4))[order(c(rep(1:6,513),rep(1,4)))]
> ### My colors:
> classcolors <- rainbow(6)
> map('county',fill=TRUE,col=classcolors[allcounties$group])
> map('state', lwd=2, add=TRUE)
>
>
>
>> Sure. Just start with
>> map('county')
>> instead.
>> I like to add something like:
>> map('state', lwd=3, add=TRUE)
>
> I am trying:
> ### My criterion for all counties in the US:
> allcounties<-data.frame(county=map('county', plot=FALSE)$names)
> allcounties$group<-sample(1:5,3082,replace=TRUE)
> ### My colors:
> classcolors <- rainbow(5)
> ### Trying to build the map - not working:
> map(database='usa',regions='county',fill=TRUE,col=classcolors[allcounties$group])
>
>
>
>> You'll need to instead coordinate with the names of the entire US:
>>> length(map('county', plot=FALSE)$names)
>> [1] 3082
>>
>> Sarah
>>
-- 
Sarah Goslee
http://www.functionaldiversity.org